Vibration driven motor

Abstract

A vibration driven motor is arranged so that a vibration member and a movable member are moved relative to each other by utilizing non-travelling vibration. A supporting member for the motor is disposed at the position of the loop of the aforesaid vibration.

What is claimed is: 
     
       1. A vibration driven motor, comprising: a bar-like vibration member;   a first two-section electro-mechanical energy conversion member, including a first section having a first polarity and a second section having a polarity opposite the first polarity, said energy conversion member being fixed functionally to said bar-like vibration member;   a second two-section electro-mechanical energy conversion member, including a first section having a first polarity and a second section having a polarity opposite the first polarity, said second energy conversion member being stacked with said first electro-mechanical energy conversion member, arranged with a spatial phase shift of substantially 90° relative to said first energy conversion member, and being fixed functionally to said bar-like vibration member;   a circuit for generating first and second electrical signals to be applied to said first and second electro-mechanical energy conversion members, respectively, including a common electrode member disposed between said first energy conversion member and said second energy conversion member such that a common electrical potential is applied to said common electrode member, wherein said first energy conversion member generates a first bending vibration having a first direction in said bar-like vibration member in response to the first applied electrical signal and said second energy conversion member generates a second bending vibration having a second direction different from the first direction in response to the second applied electrical signal, whereby a combined vibration of the first bending vibration and the second bending vibration is caused in said bar-like vibration member; and   a contact member contactable to said vibration member and having a center of rotation that is coaxial with said vibration member, said contact member being driven by frictional contact with said vibration member caused by the combined vibration in said vibration member.   
     
     
       2. A vibration driven motor according to claim 1, wherein said second applied electrical signal has a phase difference in time to said first applied electrical signal. 
     
     
       3. A vibration driven motor according to claim 2, wherein said phase difference in time is 90 degrees. 
     
     
       4. A vibration driven motor according to claim 1, wherein said spatial phase difference is 90 degrees. 
     
     
       5. A vibration driven motor according to claim 1, wherein said first energy conversion element includes a linear insulation portion for insulating said first section and said second section. 
     
     
       6. A vibration driven motor according to claim 1, wherein said second energy conversion member includes a linear insulation portion for insulating said first section and said second section. 
     
     
       7. A vibration driven motor according to claim 1, wherein a direction of polarization in said first and second energy conversion members is in a direction of the thickness of each member. 
     
     
       8. A vibration driven motor, comprising: a bar-like vibration member;   a first two-section electro-mechanical energy conversion member, including a first section having a first polarity and a second section having a polarity opposite the first polarity, said energy conversion member being fixed functionally to said vibration member;   a second two-section electro-mechanical energy conversion member, including a first section having a first polarity and a second section having a polarity opposite the first polarity, said second energy conversion member being stacked with said first electro-mechanical energy conversion member, arranged with a spatial phase shift of substantially 90° relative to said first energy conversion member, and being fixed functionally to said bar-like vibration member;   a circuit for generating first and second electrical signals to be applied to said first and second electro-mechanical energy conversion elements, respectively, including a common electrode member disposed between said first energy conversion member and said second energy conversion member such that a common electrical potential is applied to said common electrode member, wherein said first energy conversion member generates a first bending vibration having a first direction in said bar-like vibration member in response to a first applied electrical signal and said second energy conversion element generates a second bending vibration having a second direction different from the first direction in response to a second applied electrical signal, whereby a combined vibration of the first bending vibration and the second bending vibration is generated in said bar-like vibration member; and   a contact member contactable to said vibration member and having a center of rotation that is coaxial with said vibration member, said contact member being driven by frictional contact with said vibration member caused by the combined vibration in said vibration member.   
     
     
       9. A vibration driven motor according to claim 8, wherein said contact member includes a rotor frictionally engaged with said vibration member. 
     
     
       10. A vibration driven motor according to claim 9, wherein said rotor includes a cylindrical rotor having an interior surface frictionally engaging an exterior surface of said vibration member. 
     
     
       11. A vibration driven motor according to claim 8, wherein said second applied electrical signal has a phase difference in time to said first applied electrical signal. 
     
     
       12. A vibration driven motor according to claim 8, wherein said first and second energy conversion members are disposed in parallel with each other and perpendicular to a longitudinal direction of said vibration member. 
     
     
       13. A vibration driven motor according to claim 12, further comprising a supporting member for biasing each of said first and second energy conversion members toward said vibration member. 
     
     
       14. A vibration driven motor according to claim 13, further comprising a fixing member for fixing said first and second energy conversion members between said vibration member and said supporting member. 
     
     
       15. A vibration driven motor according to claim 13, wherein said fixing member is a bolt having a screw portion engageable with a screw portion of said vibration member. 
     
     
       16. A vibration driven motor, comprising: a bar-like vibration member;   a first two-section electro-mechanical energy conversion member, including a first section having a first polarity and a second section having a polarity opposite the first polarity, said energy conversion member being fixed functionally to said vibration member;   a second two-section electro-mechanical energy conversion member, including a first section having a first polarity and a second section having a polarity opposite the first polarity, said second energy conversion member being stacked with said first electro-mechanical energy conversion member, arranged with a spatial phase shift of substantially 90° relative to said first energy conversion member, and being fixed functionally to said bar-like vibration member   a supporting member for biasing each of said first and second energy conversion members toward said vibration member;   a fixing member for fixing said first and second energy conversion members between said vibration member and said supporting member;   a positioning member for supporting said fixing member at a predetermined position;   a circuit for generating first and second electrical signals to be applied to said first and second electro-mechanical energy conversion elements, respectively, wherein said first energy conversion member generates a first bending vibration having a first direction in said bar-like vibration member in response to a first applied electrical signal and said second energy conversion element generates a second bending vibration having a second direction different from the first direction in response to a second applied electrical signal, whereby a combined vibration of the first bending vibration and the second bending vibration is generated in said bar-like vibration member; and   a contact member contactable to said vibration member and having a center of rotation that is coaxial with said vibration member, said contact member being driven by frictional contact with said vibration member caused by the combined vibration in said vibration member.   
     
     
       17. A vibration driven motor according to claim 16, wherein said supporting member engages said fixing member at a portion corresponding to an antinode of the combined vibration. 
     
     
       18. A vibration driven motor according to claim 16, wherein said supporting member includes a sheet made of a low friction material fixed at a portion of a device to which said motor is mounted. 
     
     
       19. A vibration driven motor according to claim 18, wherein said sheet is made of polytetrafluoroethylene. 
     
     
       20. A vibration device for a vibration driven actuator, said device comprising: a bar-like vibration member elongated in a first direction;   a first two-section electro-mechanical energy conversion element, including first and second sections having opposite polarity, said first energy conversion element being functionally engaged with said vibration member;   a second two-section electro-mechanical energy conversion element, including first and second sections having opposite polarity, said second energy conversion element being stacked with said first electro-mechanical energy conversion element arranged with a spatial phase shift of substantially 90° relative to said first energy conversion member, and functionally engaged with said bar-like vibration member;   a circuit for generating first and second electrical signals to be applied to said first and second electro-mechanical energy conversion elements, respectively, including a common electrode member disposed between said first energy conversion member and said second energy conversion member such that a common electrical potential is applied to said common electrode member, wherein said first energy conversion element generates a first bending vibration having a first direction in said vibration member in response to a first applied electrical signal, and said second energy conversion element generates a second bending vibration having a direction different from the first direction in said vibration member in response to a second applied electrical signal, whereby a combined vibration of said first and second bending vibrations is generated in said vibration member; and   a contact member contactable to said vibration member and having a center of rotation that is coaxial with said vibration member, said contact member being driven by frictional contact with said vibration member caused by the combined vibration in said vibration member.   
     
     
       21. A vibration device according to claim 20, wherein said first and second energy conversion elements are arranged with a spatial phase difference. 
     
     
       22. A vibration device according to claim 21, wherein said first electrical signal has a phase difference in time from said second electrical signal. 
     
     
       23. A vibration device according to claim 22, wherein said phase difference in time between said first and second electrical signals is 90 degrees. 
     
     
       24. A vibration device according to claim 21, wherein said first energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       25. A vibration device according to claim 21, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       26. A vibration device according to claim 24, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof, the insulation portion of said first energy conversion element being disposed in a first direction, and the insulating portion of said second energy conversion element being disposed in a second direction crossing the insulation portion of said first energy conversion element. 
     
     
       27. A vibration driven actuator, comprising: a bar-like vibration member elongated in a first direction;   a first two-section electro-mechanical energy conversion element, including first and second sections having opposite polarity, said first energy conversion element being functionally engaged with said bar-like vibration member;   a second two-section electro-mechanical energy conversion element, including first and second sections having opposite polarity, said second energy conversion element being stacked with said first electro-mechanical energy conversion element, arranged with a spatial phase shift of substantially 90° relative to said first energy conversion member, and functionally engaged with said bar-like vibration member;   a circuit for generating first and second electrical signals to be applied to said first and second electro-mechanical energy conversion elements, respectively, including a common electrode member disposed between said first energy conversion member and said second energy conversion member such that a common electrical potential is applied to said common electrode member, wherein said first energy conversion element generates a first bending vibration having a first direction in said bar-like vibration member in response to a first applied electrical signal, and said second energy conversion element generates a second bending vibration having a direction different from the first direction in said bar-like vibration member in response to a second applied electrical signal, whereby a combined vibration of said first and second bending vibrations is generated in said bar-like vibration member; and   a contact member contactable to said vibration member and having a center of rotation that is coaxial with said vibration member, said contact member being driven by frictional contact with said vibration member caused by the combined vibration in said vibration member.   
     
     
       28. A vibration driven actuator according to claim 27, wherein said first and second energy conversion elements are arranged with a spatial phase difference. 
     
     
       29. A vibration driven actuator according to claim 28, wherein said first electrical signal has a phase difference in time from said second electrical signal. 
     
     
       30. A vibration driven actuator according to claim 29, wherein said phase difference in time between said first and second electrical signals is 90 degrees. 
     
     
       31. A vibration driven actuator according to claim 28, wherein said first energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       32. A vibration driven actuator according to claim 28, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       33. A vibration driven actuator according to claim 31, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof, the insulation portion of said first energy conversion element being disposed in a first direction, and the insulation portion of said second energy conversion element being disposed in a second direction crossing the insulation portion of said first energy conversion element. 
     
     
       34. A vibration device for a vibration driven actuator, said device comprising: a bar-like vibration member elongated in a first direction;   a first electro-mechanical energy conversion element, including only first and second sections having opposite polarity, said first energy conversion element being functionally engaged with said vibration member;   a second electro-mechanical energy conversion element, including only first and second sections having opposite polarity, said second energy conversion element being stacked with said first electro-mechanical energy conversion element and functionally engaged with said vibration member;   a circuit for generating first and second electrical signals to be applied to said first and second electro-mechanical energy conversion elements, respectively, including a common electrode member disposed between said first energy conversion member and said second energy conversion member such that a common electrical potential is applied to said common electrode member, wherein said first energy conversion element generates a first bending vibration having a first direction in said vibration member in response to a first applied electrical signal, and said second energy conversion element generates a second bending vibration having a direction different from the first direction in said vibration member in response to a second applied electrical signal, whereby a combined vibration of said first and second bending vibrations is generated in said vibration member; and   a contact member having a center of rotation which is coaxial with said bar-like vibration member, said contact member being driven by frictional contact with said vibration member caused by the combined vibration in said vibration member.   
     
     
       35. A vibration device according to claim 34, wherein said first and second energy conversion elements are arranged with a spatial phase difference. 
     
     
       36. A vibration device according to claim 35, wherein said first electrical signal has a phase difference in time from said second electrical signal. 
     
     
       37. A vibration device according to claim 36, wherein said phase difference in time between said first and second electrical signals is 90 degrees. 
     
     
       38. A vibration device according to claim 35, wherein said first energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       39. A vibration device according to claim 35, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       40. A vibration device according to claim 38, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof, the insulation portion of said first energy conversion element being disposed in a first direction, and the insulating portion of said second energy conversion element being disposed in a second direction crossing the insulation portion of said first energy conversion element. 
     
     
       41. A vibration driven actuator, comprising: a bar-like vibration member elongated in a first direction;   a first electro-mechanical energy conversion element, including only first and second sections having opposite polarity, said first energy conversion element being functionally engaged with said bar-like vibration member;   a second electro-mechanical energy conversion element, including only first and second sections having opposite polarity, said second energy conversion element being stacked with said first electro-mechanical energy conversion element and functionally engaged with said vibration member;   a circuit for generating first and second electrical signals to be applied to said first and second electro-mechanical energy conversion elements, respectively, including a common electrode member disposed between said first energy conversion member and said second energy conversion member such that a common electrical potential is applied to said common electrode member, wherein said first energy conversion element generates a first bending vibration having a first direction in said bar-like vibration member in response to a first applied electrical signal, and said second energy conversion element generates a second bending vibration having a direction different from the first direction in said bar-like vibration member in response to a second applied electrical signal, whereby a combined vibration of said first and second bending vibrations is generated in said bar-like vibration member; and   a contact member having a center of rotation which is coaxial with said bar-like vibration member, said contact member being driven by frictional contact with said vibration member caused by the combined vibration in said vibration member.   
     
     
       42. A vibration driven actuator according to claim 41, wherein said first and second energy conversion elements are arranged with a spatial phase difference. 
     
     
       43. A vibration driven actuator according to claim 42, wherein said first electrical signal has a phase difference in time from said second electrical signal. 
     
     
       44. A vibration driven actuator according to claim 43, wherein said phase difference in time between said first and second electrical signals is 90 degrees. 
     
     
       45. A vibration driven actuator according to claim 42, wherein said first energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       46. A vibration driven actuator according to claim 42, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof. 
     
     
       47. A vibration driven actuator according to claim 45, wherein said second energy conversion element further includes a linear insulation portion for insulating the first and second sections thereof, the insulation portion of said first energy conversion element being disposed in a first direction, and the insulation portion of said second energy conversion element being disposed in a second direction crossing the insulation portion of said first energy conversion element.